A Mathematical Model for Deposition From Turbulent Flows

1968 ◽  
Vol 90 (2) ◽  
pp. 164-170
Author(s):  
J. A. Broadway ◽  
R. I. Vachon ◽  
D. Dyer ◽  
H. Zallen
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Kinetic Theory ◽  
Turbulent Flows ◽  
Deposition Rate ◽  
Reference Point ◽  
Air Pollutants ◽  
Kinetic Theory Of Gases ◽  
Flow Boundary ◽  
Contamination Concentration

A mathematical model was developed to estimate the dispersion and deposition of a contaminated flow. The model, which is independent of the nature of the contaminate source, is based on an analogy between the kinetic theory of gases and real turbulent flows. The average contamination concentration and deposition rate to the flow boundary as a function of the distance downwind of a reference point are given by calculations based on the model. Assumptions and limitations of the model and their significance are discussed. The results of calculations using the model are qualitatively supported by available experimental data. The model is applicable to radioactive and nonradioactive air pollutants.

scholarly journals Port-Hamiltonian Mathematical Model of a Fluid Ring Attitude System

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6906
Author(s):  
Juan Cristobal Alcaraz Alcaraz Tapia ◽  
Carlos E. Castañeda ◽  
Héctor Vargas-Rodríguez
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Regression Analysis ◽  
Linear Regression ◽  
Turbulent Flows ◽  
Linear Regression Analysis ◽  
Hamiltonian Formalism ◽  
System Model ◽  
Energy Shaping ◽  
Spatial Environment

In this article, we propose a mathematical model using the port-Hamiltonian formalism for a satellite’s three-axis attitude system comprising fluid rings. Fluid rings are an alternative to reaction wheels used for the same purpose, since, for the same mass, they can exert a greater torque than a reaction wheel as the fluid can circulate the periphery of the satellite. The port-Hamiltonian representation lays the foundation for a posterior controller that is feasible, stable, and robust based on the interconnection of the system to energy shaping and/or damping injection components, and by adding energy routing controllers. The torques exerted by the fluid rings are modeled using linear regression analysis on the experimental data got from a prototype of a fluid ring. Since the dynamics of turbulent flows is complex, the torques obtained by the prototype lead to a simpler first approach, leaving its uncertainties to a controller. Thus, the attitude system model could be tested in a future prototype before considering a spatial environment.

scholarly journals A kinetic theory model for rain out and wash out of soluble gaseous air pollutants

MAUSAM ◽  
2021 ◽  
Vol 42 (2) ◽  
pp. 151-154
Author(s):  
A. K. MUKHERJEE
Keyword(s):  
General Theory ◽  
Kinetic Theory ◽  
Air Pollutants ◽  
Current Theory ◽  
Theory Model ◽  
Kinetic Theory Of Gases ◽  
Special Case

A new theory, using kinetic theory of gases, for dissolution of gaseous air pollutants and applicable both for wash out and rain out processes has been proposed. It has been shown that the current theory of wash out of gases given by Hales (1972) is a special case of the general theory proposed here.  

The substantiation of the formalized estimation of effectiveness of technological and production systems

2018 ◽  
Vol 15 (1) ◽  
pp. 169-181
Author(s):  
M. I. Sidorov ◽  
М. Е. Stavrovsky ◽  
V. V. Irogov ◽  
E. S. Yurtsev
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Production Systems ◽  
Van Der Pol

Using the example of van der Pol developed a mathematical model of frictional self-oscillations in topochemically kinetics. Marked qualitative correspondence of the results of calculation performed using the experimental data of researchers.

scholarly journals Exhaust Noise Reduction by Application of Expanded Collecting System in Pneumatic Tools and Machines

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1592
Author(s):  
Dominik Gryboś ◽  
Jacek S. Leszczyński ◽  
Dorota Czopek ◽  
Jerzy Wiciak
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Noise Reduction ◽  
Sound Pressure ◽  
Acoustic Pressure ◽  
Pressure Level ◽  
Computational Results ◽  
Noise Measurements ◽  
Exhaust Noise ◽  
Collecting System

In this paper, we demonstrate how to reduce the noise level of expanded air from pneumatic tools. Instead of a muffler, we propose the expanded collecting system, where the air expands through the pneumatic tube and expansion collector. We have elaborated a mathematical model which illustrates the dynamics of the air flow, as well as the acoustic pressure at the end of the tube. The computational results were compared with experimental data to check the air dynamics and sound pressure. Moreover, the study presents the methodology of noise measurement generated in a pneumatic screwdriver in a quiet back room and on a window-fitting stand in a production hall. In addition, we have performed noise measurements for the pneumatic screwdriver and the pneumatic screwdriver on an industrial scale. These measurements prove the noise reduction of the pneumatic tools when the expanded collecting system is used. When the expanded collecting system was applied to the screwdriver, the measured Sound Pressure Level (SPL) decreased from 87 to 80 dB(A).

Modal Analysis of the Axial Compressor Blade: Advanced Time-Dependent Electronic Interferometry and Finite Element Method

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Mykhaylo Tkach ◽  
Serhii Morhun ◽  
Yuri Zolotoy ◽  
Irina Zhuk
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Finite Element ◽  
High Reliability ◽  
Axial Compressor ◽  
Time Dependent ◽  
Experimental Setup ◽  
Vibration Modes ◽  
Compressor Blades ◽  
Isoparametric Finite Element

AbstractNatural frequencies and vibration modes of axial compressor blades are investigated. A refined mathematical model based on the usage of an eight-nodal curvilinear isoparametric finite element was applied. The verification of the model is carried out by finding the frequencies and vibration modes of a smooth cylindrical shell and comparing them with experimental data. A high-precision experimental setup based on an advanced method of time-dependent electronic interferometry was developed for this aim. Thus, the objective of the study is to verify the adequacy of the refined mathematical model by means of the advanced time-dependent electronic interferometry experimental method. The divergence of the results of frequency measurements between numerical calculations and experimental data does not exceed 5 % that indicates the adequacy and high reliability of the developed mathematical model. The developed mathematical model and experimental setup can be used later in the study of blades with more complex geometric and strength characteristics or in cases when the real boundary conditions or mechanical characteristics of material are uncertain.

scholarly journals Modelling time efficiency of cobot-supported kit preparation

2019 ◽  
Vol 106 (5-6) ◽  
pp. 2227-2241 ◽  
Author(s):  
Patrik Fager ◽  
Martina Calzavara ◽  
Fabio Sgarbossa
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Cycle Time ◽  
Laboratory Experiments ◽  
Spare Parts ◽  
Batch Preparation ◽  
Assembly Quality ◽  
Numerical Example ◽  
Business To Business ◽  
Support Time

AbstractKitting – meaning to supply assembly with components in presorted kits – is widely seen as beneficial for assembly quality and efficiency when there is a multitude of component variants. However, the process by which kits are prepared – the kit preparation – is labour-intensive, and kit errors are problematic at assembly processes. The use of robotics to support kit preparation has received some attention by researchers, but literature is lacking with respect to how collaborative robots – cobots – can support kit preparation activities. The purpose of this paper is to identify the potential of a cobot to support time-efficient batch preparation of kits. To address the purpose, the paper presents a mathematical model for estimation of the cycle time associated with cobot-supported kit preparation. The model is applied in a numerical example with experimental data from laboratory experiments, and cobot-supported kit preparation is compared with manual kit preparation. The findings suggest that cobot-supported kit preparation is beneficial with diverse kits and smaller components quantities per SKU (Stock Keeping Unit) and provides less variability of the outcome, when compared to manual kit preparation. The paper reveals several insights about cobot-supported kit preparation that can be valuable for both academics and practitioners. The model developed can be used by practitioners to assess the potential of cobots to support kit-batch preparation in association with assembly, spare parts, repair and maintenance, or business to business industry.

Mathematical Model of the Sintering Process of Iron-Copper Bearings

2007 ◽  
Vol 23 ◽  
pp. 119-122
Author(s):  
Cristina Teișanu ◽  
Stefan Gheorghe ◽  
Ion Ciupitu
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Mathematical Model ◽  
Regression Analysis ◽  
Function Optimization ◽  
Chemical Compositions ◽  
Sintering Process ◽  
Molybdenum Disulphide ◽  
Iron Copper ◽  
Antifriction Properties

The most important features of the self-lubricating bearings are the antifriction properties such as friction coefficient and wear resistence and some mechanical properties such as hardness, tensile strength and radial crushing strength. In order to improve these properties new antifriction materials based on iron-copper powders with several additional components (tin, lead and molybdenum disulphide) have been developed by PM techniques. To find the optimal relationship between chemical compositions, antifriction and mechanical properties, in this paper a mathematical model of the sintering process is developed, which highlighted the accordance of the model with data by regression analysis. For the statistical processing of the experimental data the VH5 hardness values of the studied materials were considered. The development of mathematical model includes the enunciation of the model, the establishment of the performance function (optimization) and the establishment of the model equations and verifying. The accordance of the model with experimental data has been highlighted by regression analysis

Some notes on a volume fraction mixture theory and a comparison with the kinetic theory of gases

1991 ◽  
Vol 29 (5) ◽  
pp. 561-573 ◽  
Author(s):  
A.C. Hansen ◽  
R.L. Crane ◽  
M.H. Damson ◽  
R.P. Donovan ◽  
D.T. Horning ◽  
...  
Keyword(s):  
Kinetic Theory ◽  
Volume Fraction ◽  
Mixture Theory ◽  
Kinetic Theory Of Gases ◽  
Fraction Mixture
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